Finding the Fourth Proportional to 72,139.01, 99,551.43 and 39,875.90

Step by Step Solution

1. Step 1: Write the proportion equation
   72,139.01 : 99,551.43 = 39,875.90 : x
2. Step 2: Convert to fraction form
   72,139.01/99,551.43 = 39,875.90/x
3. Step 3: Cross multiply
   72,139.01x = 99,551.43 × 39,875.90
4. Step 4: Simplify right side
   72,139.01x = 3,969,702,369.78
5. Step 5: Solve for x
   x = 3,969,702,369.78/72,139.01
6. Step 6: Final answer
   x = 55,028.52